porschephiliac

Alright, you can either earn this achievement by playing every song with a buddy, or, you could turn on the no-fail cheat and play every song by yourself.

1. Select "Options", "Cheats", "Enter New Cheat" from the Main Menu.
2. Strum each note or chord to unlock "No Fail" Mode.
3. Pressing G from the "Cheats" Menu will disable this cheat.

G + R, B, G + R, G + Y, B, G + Y, R + Y, O, R + Y, G + Y, Y, G + Y, G + R

Make sure you play a few notes on each instrument, for good measure.

EDIT: You should probably include to go to Multiplayer > Co-op in the guide considering half the commenters are confused about this.
For what it's worth, I did NOT have to do this in one session, I did NOT have to hit any notes on EITHER controller, and I did NOT have to keep both players on the same difficulty (The Elven Jedi's solution, while confusing, is correct). I did have to turn the cheat off and fail a song -- this last step should be in the guide, not just the comments.
Posted by Mental Knight 5

This is an accumulative achievement that adds all the combined earnings in the game. Will be unlocked eventually during normal career play. You can play multiple careers for this to accumulate, it doesn't have to be earned all in one career.

This achievement requires you and a buddy to score 600k points in a co-op song. My suggestion is to play Free Bird on Medium and score a near perfect run. If that doesn't work, try playing it on hard while your buddy plays it on medium.

This requires you and a buddy to score 400k in a co-op song. My suggestion is to try Free Bird on medium with a buddy. If you do it just right, you and your buddy can score the 600k achievement too.

For this achievement, you must score 300k points in one song. I found that is quite easily done on Free Bird with medium difficulty. You can also, with practice, score the 400k achievement and the 1000 note streak on this song pretty easily.

This requires you and a buddy to consecutively hit 1000 notes in a co-op song. This one is a long haul, as 1000 notes even in co-op is a long time to play perfectly. A tip: don't worry about star power or any other distractions, just focus on playing all your notes. There are a few songs that can be played on Medium for this, but the majority of them are on Hard.

Good Luck!

EDIT:

Famous Last Words (DLC). Easy Guitar/Medium Bass, 1246 notes from 100%. (Confirmed by Codehead UK and spammy2505 - thanks!)

Surrender Medium/Medium confirmed by OFFICER ZERO.

This achievement requires you and a buddy to play 500 consecutive notes counted together during a co-op song. I suggest playing a medium song, regardless of skill, that way you and your buddy can nail it without concern.

This achievement requires that you buy all of the bonus songs from the shop, each song will set you back $500 and seen as there are 26 of them you're looking at spending $13,000 to get this achievement.

The only way to earn money in this game is to play and complete songs, the higher the difficulty the more you'll receive, the amount of stars you get also determines how much you'll get, unfortunately there is no "quick" method to acquire money, the most time efficient way is to select the difficulty you can play best on and play through the career getting money as you play, once you've saved up enough money, go to the shop and buy all the bonus songs, achievement unlocked!

You don't need to buy all the songs in one go, you can buy them in stages, it doesn't make any difference!

Here's a list of songs in the order they should appear in the store;

* Raw Dog
* Arterial Black
* Collide
* Drink Up
* Elephant Bones
* Fall Of Pangea
* FTK
* Gemini
* Kicked To The Curb
* Push Push (Lady Lightning)
* Laughtrack
* Less Talk More Rokk
* Jordan
* Mr. Fix It
* The New Black
* One For The Road
* Parasite
* Radium Eyes
* Red Lottery
* Six
* Soy Bomb
* The Light That Blinds
* Thunderhorse
* Trogdor
* X-Stream
* Yes We Can

This is best achieved during Medium or Hard difficulty. Just do your best to keep your multiplier, activate star power at opportune times, and eventually the big 200k will fall. I found that it is fairly easy to do on Medium with Black Sabbaths' War Pigs.

You must collect enough star power to activate it, and do so when you have a 4x multiplier, that way it doubles to 8x. You will most likely get this one early in your play of this game.

Go to main menu and practice through 3 songs. It can even be the same song. Cheev pops at the end of 3rd song.

This achievement requires you to not only hit every single note, but complete the song full combo. I suggest 'Song 2' as it is the shortest (2 minutes) and has a very easy track.

I found that Desert Strike level 14 is easiest with this one, although Atlantis 4 is pretty easy too, you just have to unlock all of Atlantis to have the unlimited grenades. In Desert Strike 14, with unlimited grenades and detonator unlocked, knock down all three baddies and enrage them with 3 hits each. Next, toss a grenade softy into the middle of the middle baddie and just before it lands, hit the detonator so it pops just above the middle guy - if done right, all three will die. Took me about 3 tries to figure it out - then I could repeat it every time.

The first one you encounter is in Desert Strike level 6, but I found that Desert Strike level 15 is an easier one to boost. Yes, boost. Kill the enemy that is above the box, then drop a grenade in the hole under that soldier and it falls on the box. Restart the level and do it again. After 10 boxes pop, so does the achievement!

I hate this sucker. What you need to do is locate the respawining SMG in the middle of the ship. The tentacles will slam down, so you must keep moving. Occasionally, a tentacle will slam into the ship's deck, and be glowing orange - shoot it, rinse and repeat for all 6 tentacles, and stage one is done.

Stage two has smaller tentacles that you must shoot ONE AT A TIME as that will draw up a larger tentacle with a mine in it - shoot the mine. Repeat for all 6 tentacles, and the thing is dead.

During your attempts to kill the beast, there will be spawning space marine enemies. Dispatch them quickly, because the distraction they cause will usually put you in the path of a tentacle (which usually kills you)

This includes propane tanks, O2 bottles, hydraulic oil tanks on forklifts, boxes of dynamite, etc... just shoot at least one accurate shot and it will blow up for you. It's very easy to do before the end of the game.

According to Skadi And Omega, Fire Extinguishers do not count towards this.

The dual 6-shooters are found initially from killing bandits starting level 2, about half-way through. You can either pick up the weapons and kill a few, then die, kill a few more, die, etc... until the achievement unlocks, but that is not necessary - the bandits (cowboy looking guys) are throughout the game. By the time you reach the end, you'll be able to easily earn this one.

There are 2 ways to get this one: The easy way, and the designed way.

The easy way: Simple wait in harbor for the season to start (you can enter plotter view by pressing X and then press Y to speed it all up) Once the season starts, dock your boat and press LT, which will end the season. Cheevo unlocked!

The designed way: Play through a season. Duh!

It's hard to explain how to earn this achievement. There are literally whales every where. In order to spot them easier, make sure your camera is zoomed all the way out into boat view. (Press Down on D-Pad twice from cabin view) You will eventually see the whale. I actually didn't ever see one - the achievement simply unlocked during my first season while I was dropping pots.

The easiest Crowded Harbor mission to do this on is the first. You have a short distance to go, and you have minimal obstacles to worry about. However, if you do accidently hit the land bar ahead of you, or the ship or dock you have to maneuver between, then reset and try again. I did my first try after I finished the tutorials... so most folks shouldn't have too much trouble.

Edit: (from Elem3ntal80) The bow thrusters can be very useful to get into those tight places using LB and RB.

This achievement will come naturally during the tutorials if you have followed the tutorial instructions correctly. If not, you can get another chance at it at a random time during one of the stormier seasons.

I'd go for the tutorial if I were you.

The best way to get this one is at any time during any season, head to this point on your plotter:
http://i18.photobucket.com/albums/b117/moltengummybears/DSCF0117.jpg
and then look for it on the North side of that island.

It will look like this:
http://i18.photobucket.com/albums/b117/moltengummybears/DSCF0116.jpg

This achievement really requires 8 people who are interested in earning it to meet up online, set up a 5 minute season, and hope that no one is disconnected during it.

No one plays this legit online, so unless you schedule it, you may never earn it.

Elem3ntal80 adds: "I managed to set this up with 7 others...for us, a second on the game clock really took about 3-4 real time seconds, so the game might actually take 15-20 min to complete."

However when I had scheduled this achievement, it only took the game clock, leading me to think it's buggy for some.

The Infection game modes requires a minimum of 4 players to start and play a match. Most people that are playing this under-rated game are usually boosting, using the method described @ x360a.org:

"The best way to boost this is have the infected player grab a shotgun and stand at the enemy spawn on Court. They only spawn to the left or right of this section so you can kill them almost instantly when they spawn. Taking turns with four players you will net about 100 points every 45 minutes. Setup a 60-min match and have one person get 95-98, then the next, then the next and the last person can finish to 100. Rotate who gets 100 to be fair."

Once 500 points has accumulated, the cheevo will pop at the end of the match.

You must come in first place in a ranked match of infection. This requires at least 4 players to start a match, in which 1 player is infected and is against the remaining players. This achievement is much easier when organized and boosted with some buddies, and the lack of MP activity in this game almost makes it a must.

You earn points by killing either as the infected, or kill the infected player and become infected yourself.